Phyllanthus niruri

Herbs, annual, monoecious, 1–5 dm; branching phyllanthoid. Stems: main stems terete, not winged, glabrous; ultimate branchlets subterete, not winged, glabrous. Leaves on main stems spiral, scalelike; stipules not auriculate, brown. Leaves on ultimate branchlets distichous, well developed; stipules not auriculate, brown; blade elliptic, 11–20 × 4.5–9 mm, base obtuse to rounded, apex obtuse, both surfaces glabrous. Inflorescences cymules or flowers solitary, unisexual, proximal with 3–7 staminate flowers, distal with 1 pistillate flower. Pedicels: staminate 1.2–1.8 mm, pistillate spreading in fruit, 4–7 mm. Staminate flowers: sepals 5(–6), pale green, flat, 1.5–3 mm; nectary extrastaminal, 5(–6) glands; stamens 3, filaments connate 1/2 length. Pistillate flowers: sepals 5, green, flat, 3–3.5 mm, pinnately veined; nectary annular, unlobed. Capsules 3.5 mm diam., smooth. Seeds uniformly brown, 1.5–1.8 mm, verrucose. 2n = 26 (Costa Rica).

Phenology: Flowering and fruiting late summer–fall.
Habitat: River and stream banks, sand.
Elevation: 60–120 m.

Tex., Mexico, West Indies, Central America, South America.

Discussion

Phyllanthus niruri is found in the flora area only in DeWitt, Fayette, and Lavaca counties (and historically from Gonzales County, where it appears to be extirpated; L. E. Brown and S. J. Marcus 1998); it is widespread in the American tropics. Like P. urinaria, it is widely used in folk medicine and is the subject of intense pharmacological research. Plants from outside the West Indies and Caribbean northern South America often have been segregated as subsp. lathyroides; the differences are trivial and recent authors (G. L. Webster 2001; V. W. Steinmann 2007) did not subdivide the species.

Selected References

None.

Lower Taxa